The present invention relates to an anti-theft seal for commercial articles having rod-like portions.
The seal is particularly suitable for engaging the rods of spectacles.
In spectacle sales points it is currently common to secure said spectacles with anti-theft seals capable of activating electronic alarm circuits arranged at the entrances.
Said devices are substantially constituted by small blocks, on the surfaces of which advertising or guarantee inscriptions or trade-marks are generally applied, which have a seat for the insertion of one of the rods of a pair of spectacles and, in said seat, a screw which engages against the surface of the rod so as to lock it.
In this manner, securing occurs by exerting stress on the rod, and this can lead to permanent deformations thereof or even to the spoiling of its outer surface due to the friction of the tip of the screw.
Grip is furthermore not optimum, since action occurs only at one point of the rod, the countless commercially available embodiments whereof may be conical with a taper which decreases from the hinge toward the end or vice versa.
As can be imagined, the screw thus acts on an inclined plane, and its securing is consequently never stable unless the rod is deformed as mentioned above.